Interior outlet inspections are known to be extremely helpful in identifying issues early before they become massive problems. Early detection of a problem in an outlet conduit allows the owner/engineer to consider options for repair of the defect versus full removal and replacement of the conduit. Interior outlet inspections are a key component of the inspection process and a valuable tool to reduce the risk of internal erosion into and along the conduit and identify valve defects and other maintenance problems. For example, if a defective joint is detected early, a point repair or installation of a liner can be considered rather than having the only option be complete removal and replacement of the conduit once internal erosion has occurred.
The State of Colorado Rules and Regulation for Dam Safety and Dam Construction require an internal inspection of the outlet conduit to be completed every 10 years for High and Significant Hazard dams. Colorado Dam safety engineers assist in these inspections when practical, but in cases where confined space conditions are unsafe due to pipe size or other hazards, the dam owner is responsible for providing an inspection using remotely operated vehicles (ROV) or other remote sensing equipment. Due to the limited availability of video inspection contractors that own ROV video inspection equipment statewide, it is often difficult for an owner to find a contractor to perform these specialty inspection services in a timely manner. There are even fewer options for dams located in remote parts of the State where mobilization costs to perform the inspection are often prohibitive, or dams located where typical video inspection vehicles cannot access. In recent years there are more options on the market for compact ROV inspection camera platforms. These compact ROV setups with modern lithium-ion battery technology roughly are portable and can be transported to the site in a midsize pickup or SUV, are relatively easy to operate, and produce high-quality video images. 20% of our high-hazard dams have outdated or no internal outlet inspections. Colorado Dam Safety purchased a compact ROV camera that can be operated by the regional Dam Safety Engineers throughout the state to assist owners in meeting the internal inspection requirements. This poster presentation intends to provide an overview of the operation and examples of how it is being used to reduce risk in the State of Colorado.
